A TACAN antenna system is a special apparatus configured to supply azimuth information and distance information to an airplane to accurately and safely guide the airplane to a desired place.
FIG. 1 is a diagram provided to explain a general TACAN antenna system.
A fixed or mobile TACAN antenna including a transponder is located at a ground station 10, an airport, or a specific location, and can receive a query signal within a predetermined frequency band for use from an airplane 20. The TACAN antenna which received the query signal may radiate a specific signal. Then, the airplane 20 may receive the specific signal and calculate azimuth information (0° to 360°) relative to the ground station 10 and distance information with respect to the ground station 10. In the airplane 20, azimuth information 22 of 225° and distance information 23 of 120 NMI can be checked through a dashboard 21 illustrated in FIG. 1.
Meanwhile, FIG. 2 is a diagram provided to explain a mechanically scanned TACAN antenna according to the prior art.
A mechanically scanned TACAN antenna 30 according to the prior art as illustrated in FIG. 2 has an outer shape in which an openable radome 31 covers a lower support 32. If the radome 31 is removed, a rotatable circular implement 32 with a parasitic radiator bonded thereto is arranged. The circular implement 32 generates an amplitude-modulated radiation pattern while being connected to a 900 rpm DC motor and rotated.
The mechanically scanned TACAN antenna uses the DC motor. Therefore, the motor needs to be regularly replaced. Further, at the time of replacement, it is inconvenient to separate the relevant components from the motor, and vibrations and noises may be generated.
Meanwhile, Korean Patent No. 10-0958846 (entitled “Antenna parasitic element and broadband omni antenna”) discloses a technology relating to a broadband omni antenna including a high frequency/low frequency monopole element and high frequency/low frequency parasitic elements symmetrically formed on left and right sides of the high frequency/low frequency monopole element.